1. Field of the Invention
The present invention relates generally to a kinetic barrel gun and more particularly to a double powder charge system, with respect to projectile motion.
2. Description of the Prior Art
In small arms ballistic application, one current avenue of improvement has been to increase the velocity of the projectile. This has generally been the course of development since ballisticians started to recognize the effect on range of muzzle velocity, and particularly since modern study on the terminal or remaining velocity and its relation to gun effectiveness.
Several techniques have been used to increase the projectile motion. One course of approach has been to refine the projectile, which may include boost sustaining means in flight and another was to refine the launcher to fire the projectile at a higher velocity. A third approach concentrated mainly on the use of higher breech pressures and longer barrels than had previously been specified. Other launcher modifications included the use of lighter gases which travelled at a higher velocity, however, propellants capable of generating such a gas are difficult to obtain and use. A more common approach was in the use of multi-stage guns where a plurality of charges were exploded successively as the projectile passed various locations within the barrel, thereby accelerating the projectile as it moved down the barrel length. By this arrangement, the velocity of the projectile through the barrel is maintained at a maximum, since the additional charges supplement the initial charge. These additional charges are needed since energy generated by the initial charge is wasted in overcoming the inertia of the projectile in getting it started.
This latter refinement is exemplified by U.S. Pat. Nos. 57,607; 2,907,250; and 3,013,472. Each of these patents generally uses the concept of multi-stage acceleration. However, each patent is particularly inefficient with respect to the loading operation, the initial pressure gradients, barrel wear and erosion, and gun size. This invention is directed to remedying these deficiencies.